The GOES-R AWG Cloud Mask Product
description
Transcript of The GOES-R AWG Cloud Mask Product
![Page 1: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/1.jpg)
The GOES-R AWG Cloud Mask Product
Andrew Heidinger (NOAA/NESDIS)
William Straka (UW-CIMSS)
![Page 2: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/2.jpg)
What You Should Know by the End of Training
• Product interpretation through examples of interest.
• Strengths and limitations of the cloud mask product
• Future improvements for the cloud mask algorithm
Images courtesy of NASA ISS and STS-107
![Page 3: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/3.jpg)
Introduction• End user products viewable in AWIPS
• Cloud Mask (4 level)• AVHRR SST is generated using the AWG Cloud Mask• All GOES Cloud Products generated from the Mask
• This product is made from the visible reflectance (during the day) infrared and water vapor observations. In addition, information from an NWP model such as the GFS and radiative transfer model are used.
• The GOES-R products will be made with information from 8 of the 16 bands available, including all 5 GOES-11 bands. GOES-13/14/15 utilizes information from all but the 13.3 m channel.
![Page 4: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/4.jpg)
What Is Currently Available
•Infrared and visible satellite imagery
•ASOS cloud cover observations
•Model Forecasts of cloud cover
Key: While there is information on cloud cover, it is extremely limited.
![Page 5: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/5.jpg)
What is wrong with the current approachs?
ASOS stations • Limited in scope and widely spaced.• Amount of sky that is taken into account gets smaller as the clouds
get closer to the instrument• Clouds above 12 km are missed.
Satellite imagery (reflectances, BTs and BTDs):• Optically thin clouds are difficult to see in single-band images. • At night, low level clouds can be missed when looking at a single
channel of data.• Channel differences, while they offer more information than just a
single channel of imagery, can result in false cloud detection over various surfaces.
• Hard to quantify for sky-cover estimates.
Numerical Models• Cloud physics are often inadequate for realistic cloud forecasts.
![Page 6: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/6.jpg)
AWG Cloud Mask (ACM)• AWG Cloud Mask (ACM) uses 9 out of the 16 ABI spectral bands, including all but the 13.3 micron channel on current GOES•Makes extensive of NWP and Radiative Transfer Model (RTM) data, to generate the expected clear-sky state for the spectral and temporal tests.•Thresholds for cloud mask tests based off of training with CALIPSO (a lidar)•Adaptable to any current imager (AVHRR, GOES-11,12,13, MODIS and VIIRS), simply be turning of un-used tests
Validation against CALIPSO performed on AQUA/MODIS – an Advanced Imager from NASA with all the channel combinations we use.)
www.nasa.gov
![Page 7: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/7.jpg)
ABI Cloud Mask Test Description
The ABI Cloud Mask is a series of tests
•14 tests that look for specific signatures of the presence of cloud (cloud, bright, non-uniform, …)
•2 tests look for non-uniformity to filter clear pixels the in the case of missed cloud.
•1 restoral test to prevent reclassification of clear pixels in regions where absolutely no cloud was detected.
•Some tests are new, some are borrowed and most are modified versions of well-known tests
![Page 8: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/8.jpg)
Known Strengths• Products are generated within minutes of receiving satellite
data. ACM runs on the current GOES and POES Imagers.
• ACM is flexible. Tests can be turned off to optimize the results for specific applications. We are open to optimizing the ACM based on NWS feedback.
• Our analysis shows we meet the GOES-R specification on current GOES though GOES-R ABI should be much better.
• Probably clear and probably cloud are correlated to sky cover. These categories may aid in sky-cover forecasts and verification.
![Page 9: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/9.jpg)
GOES-R Cloud Mask Product:
What is Provided
![Page 10: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/10.jpg)
ACM in AWIPS (upper left image). Colors are white (cloudy), red (probably cloudy), cyan (probably clear), black (clear).
AC
MV
isib
le R
efle
ctan
ceIR
Window
H2 O
IR
![Page 11: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/11.jpg)
ACM in AWIPS (upper left image). Colors are white (cloudy), red (probably cloudy), cyan (probably clear), black (clear).
ACM
IR WINDOW IR WINDOW
Visible Reflectance
![Page 12: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/12.jpg)
ACM in AWIPS (upper left image). Colors are white (cloudy), red (probably cloudy), cyan (probably clear), black (clear).
ACM
Cloud Height Cloud Temperature
Cloud Type
![Page 13: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/13.jpg)
Cloud Mask Applications
• The Cloud mask can be used to determine the extent of cloudiness
What is currently happening, what is coming towards a location in terms of if a pixel is cloudy or not.
• Can be used with cloud amount forecast product
Potential to use as an input to sky-cover forecast model
Can be used as a verification of cloud sky cover forecast.
![Page 14: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/14.jpg)
Near-Term Improvements
•End user feedback is essential and will be used to guide future improvements.
•Known issues include Missing low cloud at night (fog detection can be used to
help remedy this). Terminator discontinuities. Sensitivity to NWP. Large errors in NWP surface
temperature can impact ACM.
![Page 15: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/15.jpg)
What You Should Know by the End of Training
• Which GOES-R cloud Mask products are available within AWIPS
• Product interpretation through examples of interest in CONUS and AK
• Strengths and limitations of the cloud mask product
• Future improvements for the cloud Mask algorithm
![Page 16: The GOES-R AWG Cloud Mask Product](https://reader036.fdocuments.us/reader036/viewer/2022062315/56815201550346895dc042f8/html5/thumbnails/16.jpg)
Conclusions
• Feedback is greatly appreciated.
• Thank you for viewing this training.
• Contacts: Andrew Heidinger ([email protected]) William Straka ([email protected])